Atrial strain analysis in heart failure with preserved ejection fraction: prognostic implications of left and right atrial dysfunction

Background

Two-dimensional speckle-tracking echocardiography (2D-STE) has been increasingly used to assess subclinical myocardial dysfunction. However, its application in heart failure with preserved ejection fraction (HFpEF) has primarily focused on left ventricular (LV) longitudinal systolic function, with limited data on left atrial (LA) and right atrial (RA) strain parameters.

Aim

To evaluate the prognostic relationship between LA and RA systolic and diastolic strain parameters and clinical outcomes in patients with HFpEF.

Methods

From an initial 2,201 screened HFpEF patients, 594 consecutive eligible patients were retrospectively enrolled. 2D-STE-derived atrial strain parameters were assessed from transthoracic echocardiography (2D-TTE) images. Patients were prospectively followed for cardiovascular (CVS) events, including hospitalization for acute heart failure, cardiovascular-related death, new-onset atrial fibrillation/flutter (AF/AFI), stroke, heart transplantation and ventricular assist device (VAD) implantation

LA (longitudinal, radial, and circumferential) and RA (longitudinal) strain were measured using 2D-STE. Long-term outcomes were evaluated for all-cause cardiovascular events and recurrent hospitalizations.

Results

Among 594 patients (mean age 58 ± 4 years, 58% male), 202 patients reached the combined endpoint over a mean follow-up of 1.3 ± 0.6 years. Both LA and RA strain parameters were significantly impaired compared to normal reference values (p < 0.0001). RA strain impairment was more pronounced than LA strain impairment. The strongest predictors of cardiovascular events were LA > RA free wall systolic and diastolic strain: Global RA systolic and diastolic strain (AUC: 0.72 and 0.67), and global LA longitudinal systolic and diastolic strain (AUC: 0.84 and 0.77). The degree of atrial mechanical dysfunction was most strongly associated with LA strain impairment (free wall > global strain), followed by RA strain impairment.

Patients with greater myocardial strain impairments also exhibited: Higher left atrial volume index (LAVI), NYHA functional class ≥ II, more severe diastolic dysfunction, lower LA, LV, and RV strain values; and reduced tricuspid annular plane systolic excursion (TAPSE) (p < 0.001).

LA (free wall) strain impairment and, to a lesser extent, RA strain impairment — were independent predictors of combined cardiovascular outcomes, including survival, after multiple statistical adjustments.

Conclusion

In HFpEF patients, LA strain parameters are stronger predictors of clinical outcomes than RA strain and conventional echocardiographic parameters. Given their superior prognostic value, LA strain assessment should be incorporated into routine clinical screening for HFpEF patients to improve risk stratification and disease management.